1. Field of the Invention.
The present invention relates to the separating and classifying of ore products and more particularly, but not by way of limitation, to a classifier for separating coal from other heavy ores.
2. History of the Prior Art.
Over the years there have been apparatus produced to classify and separate mixed ore components that have been mined from both surface and deep mining operations.
Earlier, in the coal mining industry when the scracity of energy was not at a crisis level, a rather large percentage of coal was wasted due to the difficulty of separating it from inter-mixed heavy ore material.
There have been many rotating barrel type apparatus developed which are efficient for the separation of coal in large chunks of one inch or greater. However, when the ore is of a size less than one inch, the barrel type classifiers have been inefficient and coal producers have been required to process the smaller particles in elaborate centrifugal apparatus known in the trade as hydrocyclones.
Hydrocyclone machines are expensive to manufacture and are likewise expensive to operate in that large capacity pumps must be used to feed an enormous amount of water through the centrifugal machine. Hence, the separation of coal from heavier ore material in particle sizes of one inch or less and especially in particle sizes of one half inch or less has been rather expensive and therefore adds greatly to the cost of the coal at the user level.